B is the right answer for this
Answer:
When we have a rational function like:

The domain will be the set of all real numbers, such that the denominator is different than zero.
So the first step is to find the values of x such that the denominator (x^2 + 3) is equal to zero.
Then we need to solve:
x^2 + 3 = 0
x^2 = -3
x = √(-3)
This is the square root of a negative number, then this is a complex number.
This means that there is no real number such that x^2 + 3 is equal to zero, then if x can only be a real number, we will never have the denominator equal to zero, so the domain will be the set of all real numbers.
D: x ∈ R.
b) we want to find two different numbers x such that:
r(x) = 1/4
Then we need to solve:

We can multiply both sides by (x^2 + 3)


Now we can multiply both sides by 4:


Now we only need to solve the quadratic equation:
x^2 + 3 - 4*x - 4 = 0
x^2 - 4*x - 1 = 0
We can use the Bhaskara's formula to solve this, remember that for an equation like:
a*x^2 + b*x + c = 0
the solutions are:

here we have:
a = 1
b = -4
c = -1
Then in this case the solutions are:

x = (4 + 4.47)/2 = 4.235
x = (4 - 4.47)/2 = -0.235
A two word phrase used to show division in a problem is :
for every, out of , ration, quotient of, divided by, unit price
hope this helps!!^_^
Let red marbles be x.
Blue : 2x
Red : x
Yellow : x+8
2x + x + x + 8 = 56
4x = 48
x = 12
Red marbles: 12
Blue : 24
Yellow: 20
To solve a problem like this, we need to start with the innermost parenthesis. Doing that, we get to 4+1, evaluating it giving us 5. This turns our expression into 5 x {3 x [9 - 5]} + 20 ÷ 4 x 2.
Now, the innermost parenthesis is 9-5. Evaluating that gives us 4. Our expression is now 5 x {3 x 4} + 20 ÷ 4 x 2.
Once again, we go to the innermost parenthesis and evaluate whatever is there. This turns our expression into <span>5 x 12 + 20 ÷ 4 x 2.
Now, we can simply use order of operations to compute that the value of the expression is equal to 70. </span>